LINGUIST 2PS3 Lecture Notes - Golgi Tendon Organ, Gamma Motor Neuron, Alpha Motor Neuron

• School: McMaster University
• Department: Linguistics
• Course: LINGUIST 2PS3
• Professor: Marek Niewczas

Document Summary

Deep within most skeletal muscles are specialized structures called muscle spindles (see fig. It consists of several types of specialized skeletal muscle fibers contained in a fibrous capsule. Group ia sensory axons wrap around the muscle fibers of the spindle the middle third. The spindles and their axons are specialized for the detection of changes in muscle length and are examples of proprioceptors. These receptors inform us about how our body is positioned and moving in space. Group i axons are the thickest myelinated axons in the body and conduct action potentials very rapidly. Within this group, ia axons are the largest and fastest. Ia axons enter the spinal cord via the dorsal roots and for excitatory synapses upon both interneurons and alpha motor neurons of the ventral horns. A single ia axon synapses on virtually every alpha motor neuron in the pool innervating the same muscle that contains the spindle.